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Microstructure Evolution and Precipitation Behavior of 0Cr16Ni5Mo Martensitic Stainless Steel during Tempering Process

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Journal of Iron and Steel Research International 2016年第4期23卷 401-408页

作者： Wu-hua YUAN Xue-hui GONG Yong-qing sun jian-xiong liang College of Materials Science and Engineering Hunan University Special Steel Institute Central Iron and Steel Research Institute

The microstructure, morphology of precipitates and retained austenite and the volume fraction of retained austenite in 0Crl6Ni5Mo stainless steel during the tempering process were analyzed using optical microscope （OM）, transmission electron microscope （TEM）, X-ray diffraction （XRD） and scanning transmission electron microscope （STEM）. The results show that the microstructure of the tempered steel is mainly composed of tempered martensite, retained austenite, and delta ferrite. In the case of samples tempered from 500 to 700℃, the precipitates are mainly M23C6, which precipitate along the lath martensite boundaries. The precipitate content increases with the tempering temperature. During the tempering process, the content of retained austenite initially increases and then decreases, the maximum content of retained austenite being 29 vol.% upon tempering at 600℃. TEM analysis of the tested steel reveals two morphology types of retained austenite. One is thin film-like retained austenite that exists along the martensite lath boundary. The other is blocky austenite located on packet at the boundary and the original austenite grain boundary. To further understand the stability of reversed austenite, the Ni content in reversed austenite was measured using STEM. Results show a significant difference in nickel concentrations between reversed austenite and martensite.

关键词： 0Cr16Ni5Mo stainless steel microstructure evolution precipitate reversed austenite thermal stability

Saturated Adaptive Output-Constrained Control of Cooperative Spacecraft Rendezvous and Docking

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IEEE/CAA Journal of Automatica Sinica 2019年第6期6卷 1462-1470页

作者： liang sun IEEE the Key Laboratory of Knowledge Automation for Industrial Processes Ministry of Education School of Automation and Electrical Engineering and also with the Institute of Artificial Intelligence University of Science and Technology Beijing

This paper investigates the robust relative pose control for spacecraft rendezvous and docking with constrained relative pose and saturated control inputs.A barrier Lyapunov function is used to ensure the constraints of states,so that the computational singularity of the inverse matrix in control command can be avoided,while a linear auxiliary system is introduced to handle with the adverse effect of actuator *** tuning rules for designing parameters in control command and auxiliary system are derived based on the stability analysis of the closed-loop *** is proved that all closed-loop signals always keep bounded,the prescribed constraints of relative pose tracking errors are never violated,and the pose tracking errors ultimately converge to small neighborhoods of *** experiments validate the performance of the proposed robust saturated control strategy.

关键词： Output-constrained control pose tracking control rendezvous and docking saturated control singularity-free control spacecraft control

2-(Trifluoroacetyl) thiophene as an electrolyte additive for high-voltage lithium-ion batteries using LiCoO_(2) cathode

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Journal of Materials Science & Technology 2020年第20期52卷 198-202页

作者： Yi sun jian Huang Hongfa Xiang Xin liang Yuezhan Feng Yan Yu School of Materials Science and Engineering Hefei University of TechnologyHefei230009China Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou450002China Hefei National Laboratory for Physical Sciences at the Microscale Department of Materials Science and EngineeringKey Laboratory of Materials for Energy ConversionChinese Academy of SciencesUniversity of Science and Technology of ChinaHefei230026China

The development of high voltage electrolytes plays a critical role to achieve advanced lithium ion batteries with high energy *** of suitable electrolyte additives is a facile and effective way to achieve enhanced electrochemical perfo rmance at high voltage *** this work,2-(tri fluoroacetyl)thiophene(TFPN) was investigated as a functional electrolyte additive for high performance lithium ion batteries using high-voltage LiCoO2 *** cycled between 3.0 V and 4.4 V at 0.5 C,the capacity retention of the LiCoO2 cathode significantly increases from 33.2 %-90.6 % by the addition of 0.5 wt%TFPN into the baseline *** on the measurements on impedance spectra and X-ray photoelectron spectra,the improved cycling performance is attributed to the preferential oxidation of TFPN on the cathode surface and thus form a protective layer to suppress the decomposition of both electrolyte solvent and lithium *** work presents that TFPN has great potential as functional additive for the development of high-voltage and high-energy-density lithium ion batteries.

关键词： Lithium ion batteries Electrolyte additive High voltage Thiophene

Experimental study of the temporary plugging capability of diverters to block hydraulic fractures in high-temperature geothermal reservoirs

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Petroleum Science 2023年第6期20卷 3687-3699页

作者： Dao-Bing Wang Hao Qin Yong-liang Wang jian-Qiao Hu Dong-liang sun Bo Yu School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing102617China Jinan Branch China Petroleum and Chemical CorporationJinan250101ShandongChina School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China LNM Institute of MechanicsChinese Academy of SciencesBeijing100190China

The effective plugging of artificial fractures is key to the success of temporary plugging and diverting fracturing technology,which is one of the most promising ways to improve the heat recovery efficiency of hot dry *** present,how temporary plugging agents plug artificial fractures under high temperature remains *** this paper,by establishing an improved experimental system for the evaluation of temporary plugging performance at high temperature,we clarified the effects of high temperature,injection rate,and fracture width on the pressure response and plugging efficiency of the *** results revealed that the temporary plugging process of artificial fractures in hot dry rock can be divided into four main stages:the initial stage of temporary plugging,the bridging stage of the particles,the plugging formation stage,and the high-pressure dense plugging *** the temperature increases,the distribution distance of the temporary plugging agent,the number of pressure fluctuations,and the time required for crack plugging ***,when the temperature increases by 100℃,the complete plugging time increases by 90.7%.

关键词： High temperature Diverter material Fracture plugging capability Hydraulic fracturing Experimental study

神经营养因子3经受体切换促进大鼠脊髓损伤后神经功能的恢复

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中国组织工程研究 2025年第11期29卷 2268-2276页

作者：丛岩于健孙志德康大伟承德医学院附属医院急诊科河北省承德市067000

背景:神经营养因子是治疗脊髓损伤的新方法,调控自噬是其发挥作用的机制之一,但具体的信号通路尚不明确。目的:探讨神经营养因子3如何通过P75NTR/Trk C受体切换来调节少突胶质细胞的自噬以及促进脊髓损伤后神经功能恢复的作用,进一步明... 详细信息

背景:神经营养因子是治疗脊髓损伤的新方法,调控自噬是其发挥作用的机制之一,但具体的信号通路尚不明确。目的:探讨神经营养因子3如何通过P75NTR/Trk C受体切换来调节少突胶质细胞的自噬以及促进脊髓损伤后神经功能恢复的作用,进一步明确具体的分子机制。方法:将24只SD大鼠随机分为3组:假手术组、脊髓损伤组和神经营养因子3组,通过大鼠后肢神经功能评分来评估神经营养因子3对脊髓损伤大鼠的治疗效果,采用Western blot检测各组大鼠脊髓组织中神经营养因子3、Olig1、MBP蛋白以及自噬标记蛋白LC3B的表达水平。在细胞实验中,将少突胶质细胞接种在培养皿中,分为糖氧剥夺组、糖氧剥夺+神经营养因子3组、糖氧剥夺+神经营养因子3+P75NTR质粒组、糖氧剥夺+神经营养因子3+Trk C质粒组、糖氧剥夺+3-甲基腺嘌呤(自噬抑制剂)组及糖氧剥夺+雷帕霉素(自噬激活剂)组。光学显微镜观察少突胶质细胞形态变化,TUNEL染色观察细胞凋亡现象,Western blot检测Trk C受体、P75NTR、LC3B表达及PI3K/AKT/m TOR和AMPK/m TOR信号途径的磷酸化状态。结果与结论:(1)动物实验显示,与假手术组相比,脊髓损伤后神经营养因子3的表达显著增加(P<0.05);与脊髓损伤组相比,外源性神经营养因子3治疗能够加快大鼠神经功能的恢复(P<0.05),并增加Olig1和MBP蛋白的表达(P<0.05);(2)细胞实验发现,3 h是损伤早期与中后期的分界点,与糖氧剥夺组相比,糖氧剥夺+神经营养因子3组少突胶质细胞能够更长时间地维持其形态,Trk C受体在早期表达水平较低而中后期显著上调(P<0.05),P75NTR则在早期上调而中后期下调(P<0.05),自噬水平呈现出先升高后降低的趋势(P<0.05);(3)通过对比糖氧剥夺+神经营养因子3组、糖氧剥夺+雷帕霉素组和糖氧剥夺+3-甲基腺嘌呤组的细胞形态和TUNEL染色结果,发现单独促进或抑制自噬对少突胶质细胞的存活均有不利影响,而类似神经营养因子3这样调节自噬的方法则能最大限度地维持细胞存活;(4)神经营养因子3在早期通过P75NTR/AMPK/m TOR信号通路促进自噬,而在后期通过Trk C/PI3K/AKT/m TOR信号通路抑制自噬。根据上述结果,得到如下结论,即神经营养因子3可以通过P75NTR/Trk C受体的切换能够双向调控少突胶质细胞的自噬,从而维持细胞存活,有助于脊髓损伤后大鼠的神经功能恢复。

关键词：神经营养因子3 自噬少突胶质细胞受体切换凋亡脊髓损伤

Crystal structure of the ubiquitin-like domain of human TBK1

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Protein & Cell 2012年第5期3卷 383-391页

作者： jian Li Jun Li Andrea Miyahira jian sun Yingfang Liu Genhong Cheng Huanhuan liang State Key Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Department of Microbiology Immunology&Molecular GeneticsUniversity of CaliforniaLos AngelesCA 90095USA Graduate School of the Chinese Academy of Sciences Beijing 100101China

TANK-binding kinase 1(TBK1)is an important enzyme in the regulation of cellular antiviral ***1 regulates the activity of the interferon regulatory factors IRF3 and IRF7,thereby playing a key role in type I interferon(IFN)signaling *** structure of TBK1 consists of an N-terminal kinase domain,a middle ubiquitin-like domain(ULD),and a C-terminal elongated helical *** has been reported that the ULD of TBK1 regulates kinase activity,playing an important role in signaling and mediating interactions with other molecules in the IFN *** this study,we present the crystal structure of the ULD of human TBK1 and identify several con-served residues by multiple sequence *** found that a hydrophobic patch in TBK1,containing residues Leu316,Ile353,and Val382,corresponding to the“Ile44 hydrophobic patch”observed in ubiquitin,was conserved in TBK1,IκB kinase epsilon(IKKε/IKKi),IκB kinase alpha(IKKα),and IκB kinase beta(IKKβ).In com-parison with the structure of the IKKβULD domain of Xenopus laevis,we speculate that the Ile44 hydrophobic patch of TBK1 is present in an intramolecular binding surface between ULD and the C-terminal elongated *** varying surface charge distributions in the ULD domains of IKK and IKK-related kinases may be relevant to their specificity for specific partners.

关键词： TBK1 ubiquitin-like domain crystal struc-ture hydrophobic patch

Vibration of Moving Strip With Distributed Stress in Rolling Process

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Journal of Iron and Steel Research International 2010年第4期17卷 24-30页

作者： sun jian-liang PENG Yan LIU Hong-min jianG Guang-biao Engineering Research Center of Rolling Equipment and Complete Technology of Ministry of Education State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 Hebei China Hot Rolling Mill Baoshan Iron and Steel Co Ltd Shanghai 200941 China

Taking the moving strip between two stands of some tandem rolling mill in rolling process as a subject for investigation, according to the Poisson-Kirchhoff sheet theory, the vibration model of the moving strip in rolling process was established. Model of distributed stress was built based on rolling theory. And then, vibration model of moving strip with distributed stress was established. The partial differential equation was discretized by Galerkin truncation. The natural frequency and stability of the moving strip were investigated and simulation in time domain was made by numerical method. Taking the moving strip between the second stand and third stand of some tandem mill as a subject for investigation, distributions of stress, natural frequencies and stability of moving strip were de- termined under six different rolling conditions which are ＂uniform distribution of stress＂, ＂flat roll flat＂, ＂flat roll convex＂, ＂flat roll concave＂, ＂convex roll flat＂ and ＂concave roll flat＂. At last, three-dimensional dynamic simulation was made and the moving law of the strip was determined. This model can be used to study the stability of moving strip, depress the shape wave of strip and develop new rolling technology from the aspect of dynamics.

关键词： moving strip distributed stress Galerkin truncation method Poisson-Kirchhoff sheet theory stability

Rapid evaluation of arsenic contamination in paddy soils using field portable X-ray fluorescence spectrometry

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Journal of Environmental Sciences 2018年第2期30卷 345-351页

作者： jian-Hong liang Pan-Pan Liu Zheng Chen Guo-Xin sun Hong Li Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification Institute of Karst Geology Chinese Academy of Geological Sciences Guilin 541004 China State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Department of Environmental Science Xi' an Jiaotong-Liverpool University Suzhou 215123 China College of Urban Construction and Environmental Engineering Chongqing University Chongqing 400045 China

Arsenic（As） in paddy fields is deteriorating food security and human health through rice ingestion. Rice is the dominant food source of arsenic exposure to half of the world’s population. Therefore, an in situ effective method for As risk evaluation in paddy soil is strongly needed to avoid As exposure through rice ingestion. Herein, we developed a rapid analytical methodology for determination of As in plant tissues using field portable X-ray fluorescence spectrometry（FP-XRF）. This method was applied to rice roots in order to evaluate the As contamination in paddy soils. The results showed that rice roots with iron plaques were superior to rhizosphere soils for generating FP-XRF signals, especially for field sites with As concentrations lower than the soil detection limit of FP-XRF（30.0 mg/kg）.Moreover, the strong linear relationships of As concentrations between the rice roots and corresponding leaves and grains proved that the rice root, rather than the soil, is a better predictor of As concentrations in rice grains. The research provides an efficient As monitoring method for As contaminated paddy fields by using wetland plant roots with iron plaques and XRF-based analytical techniques.

关键词： XRF Arsenic Risk evaluation Rice roots Rhizosphere soils Iron plaque

Chemical probe systems for assessing liquid–liquid mixing efficiencies of reactors

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Frontiers of Chemical Science and Engineering 2023年第10期17卷 1323-1335页

作者： Yi-Dong Zhang Chun-Liu Zhang liang-liang Zhang Bao-Chang sun Guang-Wen Chu jian-Feng Chen Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

Liquid-liquid mixing,including homogeneous and heterogeneous mixing,widely exists in the chemical *** to quantitatively characterize the mixing performance is important for reactor assessment and *** a convenient and direct method for mixing characterization,the chemical probe method uses some special test reactions to characterize the mixing ***,the working principle and selection requirements of this method are introduced,and some common chemical probe systems for homogeneous and heterogeneous mixing processes are *** characteristics and applications of these systems are ***,the development of the new system is proposed.

关键词： mixing chemical probe liquid-liquid heterogeneous